Perfumed products are well-known in the art. However, consumer acceptance of such perfumed products like softening products is determined not only by the performance achieved with these products but also by the aesthetics associated therewith. The perfume components are therefore an important aspect of the successful formulation of such commercial products.
It is also desired by consumers for treated fabrics to maintain the pleasing fragrance over time. Indeed, perfume additives make such compositions more aesthetically pleasing to the consumer, and in some cases the perfume imparts a pleasant fragrance to fabrics treated therewith. However, the amount of perfume carried-over from an aqueous laundry bath onto fabrics is often marginal and does not last long on the fabric. Furthermore, fragrance materials are often very costly and their inefficient use in laundry and cleaning compositions and ineffective delivery to fabrics results in a very high cost to both consumers and laundry and cleaning manufacturers. Industry, therefore, continues to seek with urgency for more efficient and effective fragrance delivery in laundry and cleaning products, especially for improvement in the provision of long-lasting fragrance to the fabrics.
One solution is to use carrier mechanisms for perfume delivery, such as by encapsulation. This is taught in the prior art and described in U.S. Pat. No. 5,188,753.
Still another solution is to formulate compounds which provide a delayed release of the perfume over a longer period of time than by the use of the perfume itself. Disclosure of such compounds may be found in WO 95/04809, WO 95/08976 and co-pending application EP 95303762.9.
However, notwithstanding the advances in the art, there is still a need for a compound which provides a delayed release of the active component, in particular a perfume ingredient.
That need is even more acute for perfume ingredients which are characteristic of the fresh notes, namely the aldehydes and ketones perfume ingredients. Indeed, whilst these provide a fresh fragrance, these perfumes are also very volatile and have a low substantivity on the surface to be treated like fabrics.
Accordingly, it is a further object of the invention to provide a softening composition comprising a perfume component which provides a fresh fragrance and is substantive to the treated surface.
The Applicant has now found that specific reaction products of an amino functional polymer with an active aldehyde or ketone, such as imines compounds, also provide a delayed release of the active such as a perfume.
Imine compounds are known in the art under the name of Schiff bases which is the condensation of an aldehyde perfume ingredient with an anthranilate. A typical description can be found in U.S. Pat. No. 4,853,369. By means of this compound, the aldehyde perfume is made substantive to the fabrics. However, a problem encountered with these Schiff bases is that the methylanthranilate compound also exhibits a strong scent, which as a result produces a mixture of fragrances, thereby reducing or even inhibiting the aldehyde and/or ketone fragrance perception.
To achieve such perfume composition with comparable aldehyde or ketones fresh notes whilst still having satisfactory fabric substantivity, perfumers have formulated around the composition. For example, by having a carrier or encapsulating material for such notes such as with cyclodextrin, zeolites or starch.
Still another solution is the use of a glucosamine as described in JP 09040687. However, this compound has been found to give a very low stability in the wash process. As a result, insufficient perfume residuality on the treated fabric has been found with these glucosamine compounds. Its use in softening composition is not disclosed.
A further solution is described in Chemical release control, Kamogawa et Al., J. Poly. Sci. Polym. Chem. Ed. Vol 20, 3121 (1982) which describes the use of amino styrene compounds condensed with aldehydes perfumes, whereby the release of the perfume is triggered by means of copolymerisation or acidification of the compound. Its application is however not mentioned.
The Applicant has now found that a reaction product between an amino functional polymer comprising at least one primary and/or secondary amine group and an active component also fulfill such a need.
Another advantage of the compounds of the invention is their ease of manufacture rendering their use most desirable.